[0001] The invention relates to cabinets and particularly to cabinets for housing medicines.
[0002] The present invention provides a medicine cabinet comprising an electrically operated
combination lock which is operable on inputting a combination code equivalent to a
pre-set code, means for setting the pre-set code, means for inputting a code, means
for comparing the inputted code with the pre-set code and means for opening the lock
when the inputted code is equivalent to the pre-set code, signal emitting means, and
timing means for operating the signal emitting means so as to produce a reminer signal
to remind a user to take or administer medication.
[0003] Advantageously, means are provided for operating the signal emitting means so as
to produce an alarm signal while the cabinet is open and the lock comprises a solenoid
having a spring loaded piston which is engageable with a keeper on de-energisation
of the solenoid.
[0004] Preferably, the means for setting the pre-set code and the means for inputting a
combination to open the lock comprises a single membrane having two portions, a code
setting portion and a code inputting portion, each membrane portion having two layers
with a conductive circuit on each layer, a spacing element having a plurality of holes
between the two layers, and means for applying pressure to discrete regions of the
membrane, so as to form electrical connections between the layers of the membrane
through the holes of the spacing element.
[0005] The membrane may be mounted in a casing one face of which is provided with a plurality
of holes, each of which is adapted to accommodate a key which may be used to make
an electrical connection between the layers of the membrane of the code setting portion,
and with a second face of the casing having a plurality of push buttons which may
be used to make electrical connections between the layers of the membrane of the code
inputting portion.
[0006] Conveniently, the means for comparing the inputted code with the pre-set code comprises
an integrated circuit element, means for translating the electrical outputs from the
code setting means and the code inputting means to provide the integrated circuit
element with the required electrical inputs, electrical logic means for producing
an incorrect code detection signal whereby the integrated circuit element using said
signal and the electrical outputs of the code inputting means is able to detect the
selection of a correct code and the timing means comprises comprises an integrated
circuit timing element operable to produce an electrical output once every set time
period and means for adjusting said time period.
[0007] Preferably, the signal emitting means comprises electrical logic means, frequency
oscillating means and signal producing means, the electrical logic means accepting
electrical inputs from the electronic circuitry to produce an electrical output which
is transmitted to the frequency oscillating means which in turn activates the signal
producing means and the frequency oscillating means includes a first oscillator and
a second oscillator and the signal producing means comprises a visual indicator and
an audible indicator, the visual indicator being operable by the first oscillator
and the audible indicator being operable by the second oscillator.
[0008] The invention will now be described more particularly, by way of example, with reference
to the accompanying drawings, in which;
Figure 1 is a perspective view of a cabinet according to the invention;
Figure 2 is a front elevation of the cabinet of Figure 1, with the door opened through
one hundred and eighty degrees;
Figure 3 is a sectional plan view on line III - III of Figure 2;
Figure 4 is a perspective fragmentary exploded view of the hinge arrangement of the
cabinet;
Figure 5 is a perspective view of a portion of the keyboard of the cabinet;
Figure 6 is a sectional view of a portion of the combination code setting and selection
mechanism of the cabinet;
Figure 7 is a block diagram of a first embodiment of electronic circuitry for the
cabinet;
Figure 8 is a circuit diagram of the electronic circuitry of Figure 7;
Figure 9 is a plan view of a marked out printed circuit board for receiving the components
of the circuit shown in Figure 8;
Figure 10 is a plan view of a membrane having a conductive ink circuit, the membrane
forming part of the combination code setting and selection mechanism; and
Figure 11 is a schematic view of the conductive ink circuit of the code selection
mechanism; and
Figure 12 is a block diagram of a second embodiment of electronic circuitry.
[0009] Referring to the drawings and initially to Figures 1, 2 and 3, the cabinet comprises
a moulded housing 1 having a bottom panel la, rear panel lb, top panel lc and two
side panels ld, the housing 1 having hinged thereto a moulded door 2 comprising a
front panel 2a with rearwardly extending bottom, top and side lips 2b, 2c and 2d.
In the closed position of the door 2, as seen in Figure 1, the lips 2b, 2c and 2d
engage end to end with the front edges of the bottom, top and side panels la, lc and
ld of the housing 1. The cabinet is manufactured from an acrilonitrile-butadiene-styrene
(ABS) copolymer.
[0010] The cabinet has a four digit coded combination lock operable by push keys 5, i.e.
to open the cabinet the four digits of the code must be sequentially keyed in using
the push keys 5. The code of the combination lock may be reset by the user. The lock
and its details of operation will be described in more detail hereinafter.
[0011] The door 2 is hinged to the housing 1 by hinge rivets 7 which pass through corresponding
holes 6a, 6b provided in the cabinet housing 1 and door 2 (see Figures 2 and 4). The
cabinet housing 1 has shelves 3 and 3a, and a vertical partition 4 between shelf 3a
and bottom panel la. The cabinet may be mounted on a wall, for which purpose screw
receiving holes 9 are provided in the rear panel lb. Alternatively, the cabinet may
be freestanding, for which purpose supports 10 are provided which keep the bottom
panel la of the housing and the bottom lip 2b of the door 2 clear of the surface on
which the cabinet stands.
[0012] The cabinet is provided with a desiccant (not shown) to control the humidity. As
may be seen in Figure 2, a compartment wall 11 is provided at the bottom left hand
side of the cabinet housing 1, to receive and locate the desiccant.
[0013] The cabinet is intended primarily for use in the storage of medicines in the home
and for preventing young children from getting access to the medicines. As a safety
feature the four digit combination code may be reset if it is feared that a child
might become familiar with a particular combination code. Because the cabinet is manufactured
from a plastics material, the cabinet may, in the event of an emergency, be forced
open, for example, by prising open the door with a screwdriver.
[0014] The push keys 5 (see Figure 5) are extra large to facilitate handicapped or arthritic
patients. The numerals of the keys 5 are raised and colour printed to assist the blind
or partially blind.
[0015] The cabinet is provided with electronic circuitry for operating the combination lock
and for producing reminder and alarm signals. The electronic circuitry is mounted
in a generally rectangular casing 20 provided in the cabinet door. A front cover 21
flush with the front face of the door 2 protects the circuitry.
[0016] The electronic circuitry is powered by a battery 100 (see Figure 3) which is located
in a compartment 101 within the casing 20, and accessible from outside the cabinet
through a hatch 102 in the front cover 21. The electronic circuitry may also of course
be operated from mains electricity.
[0017] The locking mechanism includes a solenoid 103 mounted at one corner of the casing
20. When the lock is operated piston 104 of the solenoid 103 engages a keeper 22 formed
in the shelf 3a.
[0018] Incorporated into the electronic circuitry is a time delay feature. If a user of
the cabinet keys in an incorrect four digit combination, then the electronic circuity
shuts down for a predetermined time interval, for example ten seconds, before the
circuitry will accept a further four digit combination. Such a feature prevents a
person from quickly keying in random four digit combinations into the circuitry in
an attempt to find the correct code.
[0019] Referring to Figure 1, the reminder and alarm signals are produced by both a light
emitting diode (LED) 105 and a piezo electric buzzer (not shown in Figure 1) located
behind grille 24 in the front cover 21. The LED 105 produces a flashing light and
the buzzer produces a buzzing sound under a number of conditions.
[0020] Reminder signals are emitted to remind a patient of a medication dosage interval.
For this purpose, the circuitry includes a timer-circuit on which the dosage interval
may be set.
[0021] Alarm signals are produced when the door 2 is opened, thus giving a warning that
the cabinet is open. To turn off the alarm signals it is necessary to close the door
2 of the cabinet.
[0022] A signal in the form of a short bleep from the buzzer is produced whenever a push
key is pressed, except when the key is pressed immediately after a dosage interval
reminder, thus indicating that someone is opening or attempting to open the cabinet.
[0023] The LED 105 also comes on whenever the battery runs low.
[0024] Two embodiments of electronic circuit will now be described, the first embodiment
being described with reference to Figures 1 to 11 and the second embodiment being
described with reference to Figure 12.
[0025] Figure 7 is a block diagram of the first embodiment which consists of the following:
(A) - code pre-setting and code inputting circuit
(B) - code detector circuit
(C) - door lock mechanism
(D) - door status detector
(E) - timer circuit
(F) - signal emitting circuit
[0026] The code pre-setting and code inputting circuit (A) will now be described in more
detail. The circuit (A) employs membrane switch technology, and consists of a single
membrane housed within the casing 20 of the cabinet door 2. The conductive circuit
printed on the membrane is shown in Figure 10. Lines A to D, 0 to 9 and Z at the top
left hand corner of Figure 10 form an edge connector for connection to the printed
circuit board 95 (see Figures 2 and 9). Two fold lines are shown on the membrane.
That part Fl of the membrane to the right of fold line II-II is the code pre-setting
circuit and that part F2 of the membrane to the left of the fold line II-II is a membrane
switch code inputting circuit (i.e. key pad). The membrane is first folded along line
I-I so that lines A, B, C and D overlap lines 0 to 9 and lines Zl, Z2 and Z3 overlap
the thickened vertical sections of lines 0 to 9. An insulating spacer Sl (see Figure
6) is inserted between the overlapping circuits. An insulating spacer Sl (see Figure
6) having a plurality of holes corresponding to the cross over points of the conductors
is placed between the upper and lower membranes. Thus pressing the upper and lower
membranes together at these cross over points will result in electrical contact between
associated upper and lower conductors. The printed membrane and insulating spacer
membrane are then folded along line II-II so that the two layers of circuit Fl overlap
the two layers of circuit F2, and an insulating pad S2 is inserted between Fl and
F2. The arrangement of the layers is best seen in Figure 6. The four digit combination
code is pre-set by bringing conductive lines on the two layers of circuit Fl into
contact with one another. The contadt is made by four keys 15 pushing the two layers
into contact with one another through four holes in membrane Sl, the four holes being
chosen from a 4x10 array of holes (one code pre-setting key and hole are shown in
Figure 6).
[0027] The schematic for the circuit (A) is shown in Figure 11. Voltage is supplied to the
circuit by line Z. The combination code for the cabinet is pre-set by first bringing
each of the four horizontal lines A, B, C and D into contact with one of the ten vertical
lines 0 to 9. When a code is inputted into the circuit, the line Z is brought into
contact with one of the ten vertical lines thus sending a signal along the vertical
line. Should that vertical line be associated with one of the four horizontal lines
A to D, then a signal will also be sent along the associated horizontal line.
[0028] The signals on lines A to D are transmitted to pins 11, 12, 13, 14 of the integrated
circuit U2. To re-set the code, the keys are moved to different holes in the 4x10
array. In a similar manner, the push keys 5 bring the conductors on the thickened
vertical sections of lines 0 to 9 into contact with conductors Zl, Z2 and Z3 on the
two layers of circuit F2 into contact with one another, thereby sending signals to
pin 10 of U2. The pre-set code and the inputted code are compared by U2.
[0029] To the user of the cabinet, the keys 15 for setting the code are each inserted in
a separate hole 16 in a different row of a 4x10 array of holes 16 in the casing 20
(see Figure 2). Alternatively, the four keys may each be slidable on a separate rail
to any one of ten positions.
[0030] Referring again to Figure 7, (B) to (F) are all mounted on an L-shaped printed circuit
board 95, the outline of which is shown in Figure 2. The layout of the printed circuit
board 95 is shown in Figure 9.
[0031] Referring to Figures 7, 8 and 9, the code detector circuit (B) comprises a large
scale integrated circuit U2 (LSl 7225) and associated passive components which translate
the outputs from the code setting and selecting mechanism to provide U2 with the required
inputs. Of these passive components diodes D2 to Dll form a key detector which informs
U2 that a push key 5 has been depressed and diodes D12 to D15 perform a similar function
for the four code digits which have been set by the keys 15. These diodes in association
with an exclusive -OR logic gate formed by logic gates of the NOR and INVERTER integrated
circuits perform an incorrect code detector input. With this input and the inputs
from the push keys 5 the integrated circuit U2 is able to detect a correct code sequence.
[0032] The door opening and locking circuit (C) consists of the solenoid 103 operated from
the code detector circuit (B) by means of a drive transistor Tsl, so as to withdraw
the piston 104 when the correct digit combination code is detected to allow the door
2 to be opened. When the door 2 is opened the piston 104 is released. To facilitate
closing of the door 2 the piston 104 is spring loaded.
[0033] The door status detector circuit (D) comprises a switch SW1 and associated resistors
and capacitors. Its function is to reset all electronic functions when the cabinet
door 2 is closed and provide an input to the signal emitting circuit (F) when the
door is open.
[0034] Switch SW1 is a contact switch (not shown in Figure 2) which is mounted on the casing
20 of the cabinet door 2 and is closed when the cabinet door is closed. Movement of
the door 2 a distance beyond 2mm opens SW1 to operate the alarm circuit (F) and release
the solenoid 103. Reclosing the door 2 closes switch SW1 which resets all the electronic
functions including the timer circuit (E).
[0035] The timer circuit (E) comprises an integrated circuit Ul (4060) and associated resistors
and capacitors. The timer circuit operates continuously but is only allowed to trigger
the alarm when switch SW2 is closed. The basic clock frequency is a half a second
which is divided by fourteen binary stages to give an alarm output every 86,400 seconds
(24 hours). This time interval can be reduced to a minimum of 900 seconds (15 minutes)
by adjustment of potentiometer RV1. To the user the potentiometer is in the form of
a manually operable rotary dial 21 mounted on the casing 20. Switch SW 2 is closed
by pushing dial 21 inwardly towards the casing.
[0036] The signal emitting circuit (F) consists of a logic OR input, a low frequency oscillator,
a high frequency oscillator, a visual signal emitter or LED 105 and an audible signal
emitter or buzzer.
[0037] The logic OR function comprises diodes D18, D19 and D20 which accept inputs from
the timer, the door status and the keyboard circuits and provide a logic 1 output
to the low frequency oscillator when any combination of these inputs are at logic
1.
[0038] A logic 1 output from the above logic OR activates the signal emitter as follows:
[0039] The first oscillator comprises an inverter gate from the INVERTER integrated circuit
U3, a NOR gate from the NOR integrated circuit U4, and associated resistors and capacitors
to control the frequency of oscillation. The passive components are designed for an
oscillation frequency of 5 Hertz.
[0040] The second oscillator is identical but has a dual inverter output stage to drive
the audible alarm Xl. The passive components for this stage are designed for an oscillation
frequency of 4,500 Hertz.
[0041] The visual signal emitter comprises a drive transistor and associated light emitting
diode (LEDl) 105 which is driven from the first oscillator.
[0042] The audible signal emitter consists of a piezo electric resonator Xl which is driven
from the second oscillator which in turn is activated by the first oscillator.
[0043] The second embodiment of electronic circuitry will be described with reference to
Figure 12. The circuitry of the first embodiment is replaced by a single customized
mask-programmed 4-bit CMOS microprocessor chip 270 which contains the necessary RAM
and ROM components for the operation of the cabinet.
[0044] The second embodiment also includes additional features such as a 4.5 digit liquid
crystal display 200 controlled by a controller 210; a thermometer 220; a heart rate
monitor 230; a smoke sensor 240 and a voice recognition chip 250.
[0045] The keypad has two additional functional keys 260, which control such functions as
clock and alarm time settings, alarm muting, thermometer, and heart rate monitor.
[0046] The microprocessor chip 270 contains counter/timer hardware and a master oscillator.
The microprocessor software uses this hardware to provide a real time programmable
clock and associated programmable alarm times.
[0047] When the real time coincides with the alarm time the software then jumps to a routine
which activates the visual and audible signal emitters which are driven directly from
the microprocessor.
[0048] The 4.5 digit LCD display 200 may be driven, either via the LCD controller I.C. 210
or directly by the microprocessor 270 and can display not only time but also heart
rate and temperature when required. The display flashes on and off when the microprocessor
detects that the battery voltage is low.
[0049] The audible signal comprises a piezo buzzer 280 resonant at 4,500 Hertz. The microprocessor
outputs drive the buzzer directly. The visual signal emitter again comprises a light
emitting diode (LED) 105 and associated resistor. The LED is driven directly at a
frequency of 5 Hertz.
[0050] The thermometer 220 comprises a temperature sensitive transducer (temperature to
voltage converter) and an analog to digital converter 290 which converts the voltage
into usable digital information. The microprocessor 270 reads this data converts it
into usable temperature data using an algorithm and displays the resulting temperature
on the LCD display 200.
[0051] The heart rate monitor 230 uses an infrared detector to measure the pulse rate of
the patient. The detector is placed on a person's wrist. As the blood pulses through
the wrist the intensity of the detected heat changes. Thus the microprocessor which
receives this information via the analog to digital converter 290 can compute the
heart rate and subsequently display it on the LCD display 200.
[0052] The smoke sensor 240 when activated by the presence of smoke causes the alarm circuit
to emit signals.
[0053] The voice recognition chip 250 enables a severely handicapped person to speak the
four digit combination code and thereby open the cabinet.
[0054] The features disclosed in the foregoing description, in the following claims and/or
in the accompanying drawings may, both separately and in any combination thereof,
be material for realising the invention in diverse forms thereof.
1. A medicine cabinet having a door, an electrically operable combination lock for
locking and releasing the door and a control device for actuating the lock on inputting
of an operating code equivalent to a pre-set code, the control device including means
for setting the pre-set code, means for inputting an operating code and means for
comparing the operating code with the pre-set code so as to actuate the lock when
the operating code is equivalent to the pre-set code, characterised in that the control
device further includes signal means and timing means for operating the signal means
so as to produce a reminder signal, to remind a user to open the cabinet and to take
or administer medication.
2. A medicine cabinet as claimed in Claim 1, in which means are provided for operating
the signal means so as to produce an alarm signal while the cabinet-door is released.
3. A medicine cabinet as claimed in Claim 2 or 3 which includes a contact switch which
is closed when the cabinet-door is closed and which is opened on releasing the cabinet-door,
the closing of the switch causing the resetting of the functions of the control means
and the opening of the switch causing the operation of the alarm means.
4. A medicine cabinet as claimed in any one of the preceding claims, in which the
means for setting the pre-set code and the means for inputting an operating code comprises
a single membrane having two portions, a code-setting portion and a code-inputting
portion, each membrane portion having two layers with a conductive circuit on each
layer, and a spacing element having a plurality of holes between the two layers, whereby
the application of pressure to discrete regions of the membrane, forms electrical
connections between the layers of the membrane through the holes of the spacing element.
5. A medicine cabinet as claimed in any one of the preceding claims, in which the
means for comparing the operating code with the pre-set code comprises an integrated
circuit element, means for translating the outputs from the code-setting means and
the operating code inputting means to provide electrical inputs to the integrated
circuit element, and logic means for producing an incorrect code detection signal,
whereby in response to the said detection signal and the said electrical inputs, the
integrated circuit element is able to detect the selection of a correct code.
6. A medicine cabinet as claimed in any one of the preceding claims, in which the
timing means comprises an integrated circuit timing element operable to produce an
electrical output once every set time-period and means for adjusting said time-period,
and in which the signal means comprises logic means and first and second frequency
oscillating means, the logic means accepting electrical inputs from the control device
to produce an electrical output which is transmitted to the first and second frequency
oscillating means, the first oscillating means actuating a visual indicator and the
second oscillating means actuating an audible indicator.
7. A medicine cabinet as claimed in any one of the preceding claims, in which the
signal means is activated when the operating code inputting means is operated.
8. A medicine cabinet as claimed in any one of the preceding claims, which includes
power-supply monitoring means and in which the signal means is activated when the
monitoring means indicates that the power supply is at a low level.
9. A medicine cabinet as claimed in any one of the preceding claims, including means
for measuring the body-temperature and/or the heart-rate of a subject, and display
means for the display thereof.
10. A medicine cabinet as claimed in any one of the preceding claims, which has a
compartment for housing a desiccant.